The Darkest Shade
by Cheeky Slytherin Lass
Summary: Because when you're a Black, there's no such thing as taboo. Bellatrix loves and Andromeda, and Andromeda is surprisingly okay with it. Blackcest. Rated M for smut in future chapters.


A/N: Written for the queen of the Black family, Gamma's Incestuous Challenge with a little (a lot) of help from brazenser's Everything Goes Challenge. Enjoy!

Andromeda's feet were bare as she walked through the garden, tending to the plants with a care that seemed to come so naturally to her. Bellatrix watched with narrowed eyes, arms folded across her chest as she leaned against the exterior of the manor.

Andromeda was so kind, so pure. In spite of their family's best efforts, she had proven to be a contrary Black. At first, Bellatrix had hated her for it.

"Why can't you be normal, Drom?" she had often complained. "Why do you have to ruin everything?"

But now, she saw her sister in a different light. The modesty and innocence were appealing, something that Bellatrix could tarnish. Andromeda, so lovely and kind, was a beautiful challenge.

The older girl pushed herself off the wall and stalked closer. "You'll snap the leaves, idiot," she scolded lightly, pulling her sister's hand back. "And Mother will be livid."

Andromeda rolled her eyes. "Plants require care, Bella," she said, shaking her head, her brown curls falling in her face. "What do you know about caring?"

Bellatrix scowled, her dark eyes hardening. "I care about you," she snapped. "I love you."

The other girl gave an amused laugh, soft and melodic as windchimes in a breeze. "Do you?"

"Of course. You're family."

"Family and love are not synonymous."

Bellatrix growled. "Can't you just pretend to be normal and stop talking like a bloody Ravenclaw? You're a Slytherin. You're a Black. You ought to behave as such!"

The amusement never left Andromeda's features. She gave a lazy shrug of her shoulders. "How does one act like a Black? Even if most of our family holds the same beliefs and principles, they're all quite different. Uncle Al-"

Acting on impulse and the desire to silence her sister, Bellatrix tangled her fingers in Andromeda's hair, pulling her forward so that their faces were inches apart. Like magic, the younger girl fell silent instantly. Bellatrix felt a flicker of excitement at the shocked expression.

Her lips fell upon Andromeda's with a surprising tenderness. She could have been rough. She could have gripped her sister's chin with bruising fingers or bitten those pretty lips.

Andromeda gasped and went completely still, which Bellatrix took as a good sign. Her grip in the curls loosening, she moved her lips slowly, almost smiling into the kiss. Gradually, Andromeda relaxed into it. Her surprise seeming to have melted completely, she even returned the kiss, her lips mirroring Bellatrix's every twitch.

But Andromeda was the one to pull away. Again, her eyes were wide, and her face was a mask of horrified disgust. With a trembling hand, she wiped her mouth, shooting her sister a betrayed look. "What was that?" she demanded.

"I told you. I love you."

"You're my sister. That kind of love is wrong."

Bellatrix smirked. "We're Blacks," she laughed. "That kind of love is almost as normal as evening tea. You enjoyed it. I was there. I felt you kiss me back."

A deep blush spread over Andromeda's cheeks. She opened her mouth, no doubt in order to deny it, before close it again without a sound.

"Does it make you feel dirty?" Bellatrix purred, her lips at Andromeda's ear. "Do you hate knowing that you're a Black after all?"

"Yes." Barely a whisper.

"You don't have to feel that way," Bellatrix said. "Give it time. You'll learn to embrace it. I can help."

Andromeda looked at Bellatrix the way she had when they were children- with the curious eyes of a younger sister looking to the eldest to teach her the ways of the world. Swallowing dryly, her blush deepening to a red, she nodded.

Bellatrix placed a chaste kiss to the corner of Andromeda's lips, stroking her hair. "Good girl," she praised with a victorious smile. 


End file.
